Automatic stacking apparatus



Nam 5, 335., F. B. CLARK 2,019,843

AUTOMATIC STACKING APPARATUS Filed Nov. 1'7, 1934 5 Sheets-Sheet 1 INVENTOR.

Nov. 5, 1935. F. B. CLARK AUTOMATIC STACKING APPARATUS Filed Nov. 17, 1934 5 Sheets-Sheet 2 ATTORNEY. v

0v. 5, 1935., CLARK 2,019,843

AUTOMATIC STACKING APPARATUS File NOV- 93 5 Sheets-Sheet 5 INVENTOR.

FEEDER/B EELHRK F. B. CLARK AUTOMAT IC STACKING APPARATUS Filed Nov. 17, 1954 5 Sheets-Sheet 4 K m 4 I R. Y. C 6 EB. 0 v T 9 11 we mm T w 7: m 1 1 mm 1 M F Nov, 5, 1935. I

. Nov. 5 1935., F. B. CLARK ma ma AUTOMATIC STACKING APPARATUS Filed Nov. 17, 1934 5 Sheets-Sheet 5 FREDER/UEULHHK Patented Nov. 5, 1935 UNITED STATES PATENT OFFICE 9 Claims.

My invention relates to apparatus or machines for stacking articles from a source of supply into predetermined position relative to each other on a platform or conveyor.

The principal general object of my present invention is to provide in a machine or apparatus for the above purpose, mechanism to receive and advance a succession of the articles in a definite path to predetermined positions, with means operable or controlled by the movements of the articles to efiect release of the articles at said predetermined positions for stacking.

The invention is illustrated in the present application in the nature of stacking apparatus for sheet materials such as towels or other flexible sheet articles, but I wish it understood that the invention broadly may be utilized for advancing and stacking various types of articles other than towels and the like.

More specifically the objects of the invention include in a machine'or apparatus of the character specified, the provision of movable supports to receive opposite marginal portions of the articles, and means to grip the articles against said supports and to move them ther-ealong predetermined distances determined by the dimensions of the articles in the direction in which they move, with means automatically controlled by the movements of said articles to move said supports away from gripping engagement relative to said gripping and conveying means to release the articles and to cause them to be deposited at a common predetermined point in their paths of travel one on the other.

Another object of the invention is to provide electrically controlled means for operating the movable supports whereby the articles will be moved in succession across the supports at a rapid rate one after the other and stacked in an even pile. This object is accomplished generally by providing that the electric circuit or circuits controlling the movements of the movable supports is or are made and broken by the movement of the articles, so that in effect the articles are measured as they pass over the supports from the source of supply, whereby articles of difierent sizes may be handled or stacked by one machine,

- as pointed out hereinafter.

movable supports to receive the articles therefrom, and which is automatically lowered by the weight of the articles deposited so that the topmost article is always dropped from the movable supports substantially the same distance as the 5' preceding articles.

Another object of the invention is to provide stacking apparatus of the above type which may be used in conjunction with flat work ironers or other standard equipment of laundries, textile 10 I mills, or the like, without altering the construction of the flat work ironers, and to also provide whereby a plurality or battery of the stackers may be used in connection with one flat work ironer or similar apparatus.

The foregoing and other objects and advantages of the invention will be specifically pointed out during the course of the following detailed description of the accompanying drawings, in Which Fig. 1 is an end elevation partly in section of a stacking-machine embodying my present invention;

Fig. 2 is a fragmentary plan view of the intake end of the stacking machine;

Fig. 3 is a side elevation partly in section of the same machine;

Fig. 4 is a fragmentary vertical sectional view through the contact roller and cooperating parts at the intake end of the stacking machine; 30

Fig. 5 is an electrical diagram showing the circuits for controlling the operation of the movable supports;

Fig. 6 is a side elevation of fragments of the outlet end of a flat work ironer and the intake end of a stacking machine showing an attachment on the stacking machine to guide the articles from the ironer to the stacker;

Fig. '7 is a top plan View, more or less diagrammatic, showing a plurality or battery of the stackers arranged for cooperation with a single flat work ironer or the like from which the articles are fed;

Fig. 8 is a perspective View of the intake end of the stacking machine showing the adaptation of a photoelectric eye mechanism thereto;

Figs. 9 and 9d are fragmentary views partly in section and partly in elevation illustrating mechanical control means for accomplishing stacking of articles; and

Fig. 10 shows an electric circuit including a light sensitive device and solenoid for controlling the operation of the movable supports.

In the drawings, the numeral [0 designates the frame of the machine composed of opposite side pieces interconnected by elongated bolts extending through brackets |2 formed as a part of the sides of the frame, nuts I3 being threaded onto the ends of the elongated bolts II to draw and hold the sides together. The corners of the frame are provided with bosses 4 screw threaded on their interiors to receive sleeves l5 having screw threads cooperating with those on the bosses M. The lower ends of the sleeves I5 designated by the numeral l5 are mounted in coup-- lings I! on casters iii.

The frame it! is thus.v supported upon the sleeves it which serve as legs, and on top of the frame I0, at one end thereof is mounted a housing or superstructure designated generally by the numeral I9. As shown best in Fig. 3, the superstructure I9 is secured to the top of the frame Ill by bolts 2!! which pass through extensions on the lower end of the superstructure and into the frame I0.

Alined pairs of brackets 25 are located adjacent the ends of the frame and on top thereof and are provided in their upper ends with openings to receive the ends 22 of shafts 23 to which are keyed blocks 24, as by means of set screws 25, the blocks carrying for rotation therewith pulleys 26. Mounted on the superstructure or housing iii isa gear reducer 2? driven by an electric motor 28 also shown mounted on the superstructure. The gear reducer 2'! drives a beveled gear 29 which meshes with a gear wheel 38 on one of the shafts 23. Trained around the pulleys 26 arebelts 3| shown as of substantially frusto-conical shape in cross-section to fit in the grooves of the pulleys 26 to be driven thereby when the gears 29 and 3|) drives said one of the shafts 23.

At regular intervals along the sides and on top of the frame It) are provided brackets 32 secured to the frame, as by means of bolts 33 and each provided in its upper end with a bearing for a pin 34. Mounted on the pins 34 are hinge members 35 which extend inwardly and which are secured to the undersides of boards or other smooth plates 36, there being one of said plates at each side of the frame and with the inner ends thereof disposed beneath and normally in contact with the lower flights of the belts 3|. Each of the boards or plates 35 extends substantially from adjacent one end of the frame to the other, and, of course, the length of the boards, and/or the distance which they are spaced apart may be varied to meet the requirements for different types or sizes of articles to be stacked.

Boards or plates 36 may be moved from the full line position of Fig. 1 to the dotted line position thereof by movement with the hinges 35 on pins 34 by mechanism about to be described. Links 31, one at each side of the superstructure or housing l9, are pivotally connected at 38 to the hinge members 35 located within the housing or superstructure I9, and are pivotally connected at 33 to couplings 39, which in turn are connected to actuating rods 45 which extend through openings in the upper walls of the housing or superstructure l9. The upper ends of the actuating rods 40 are mounted through openings in the ends of a cross-beam 4| and receive nuts 42 coupling the rods to the cross-beam. Coil springs 53 are compressed between the topof the superstructure and the ends of the cross-beam 4| surrounding the actuating rods 43 to normally hold the parts in the, full line position of Fig. l, with the boardsor plates 33 in engagement with or urged toward the belts 3|.

A solenoid S is mounted on the superstructure and is operatively connected to a plunger 44 connected as at 45 to the cross-beam 4| at its approximate center. The operation of the solenoid is such that when it is energized it draws the plunger 44 and cross-beam 4| down against the action of the springs 43, whereby the actuating rods which are coupled to the cross-beam by the nuts 42, move the links 31 and hinge members 35 to the dotted line position of Fig. 1; and when the solenoid is de-energized, the springs 43 move the beam 4| and actuating rods 46 upwardly to return the links 37 and hinge members 35 and plates 36 to the full line position of Fig. 1.

The mechanism for controlling the electric circuit hereinafter described to operate the solenoid S0, is located adjacent the intake end of frame H3 or end remote from the superstructure or housing 59, and is shown best in Figs. 2,

3 and 4. Referring to these figures, it will be noted that one of the shafts 23 has keyed thereto, a cylinder or wheel 48 as by means of a screw 49, and the shaft 23 is insulated from the inner flange 5B of the wheel 48 by an insulating or non-conducting cylinder 5|. An insulating board or plate 52 is supported above and across the intake end of the machine by bolts 53, the heads of which engage the upper surface of the board and the lower ends of which are threaded into the frame I0. Coil springs 54 surround the bolts 53 and resiliently support the board 52 above the frame IS. A pair of spaced electrical contacts 55 are attached to the board 52 by means of screws 52', to which the wires hereinafter referred to and leading from the source of electric supply are attached. The spring contacts 55 are disposed beneath the contact wheel 43 with their ends normally in contact with the outer surface of the wheel or cylinder 43.

Referring now to Fig. 5, wherein the electric wiring diagram is shown, the letters SW indicate a switch connected to terminals 55 and 5? and movable into and out of engagement with terminals 58 and 59 which are connected to wires leading in from the source of electric supply. Wires 6!! and 5| connect the terminals 56, 51 with a transformer TR. A wire 52 connects one side of the transformer to one of the contacts 55, while the other contact 55 is connected by a wire 63 to the relay R, which in turn is connected by a wire 64 to the other side of the transformer TR. Thus, with the switch SW closed connecting the terminals and 51 with the terminals 58 and 55, a current of predetermined voltage fiows through wires 62, 63 and 54 and the relay when the contacts 55 are in 55 engagement with the cylinder 33. When this circuit is completed, as just mentioned, the relay R energizes the solenoid SO by a circuit completed through wire 65 connected with the terminal 58 of the relay, and with the wire 5| at E57, and wire 58 connected to the wire 59 at 59 and to the solenoid, which is also connected with the terminal iii of the relay by a wire ll. Thus the solenoid is energized and de-energized according to whether or not the contacts 55 are in engagement with the cylinder 48, and it is the feeding of the articles between the cylinder 48 and the contacts 55 which breaks the circuit and de-energizes the solenoid, as will be presently pointed out more in detail.

If desired the motor 28 may be a variable speed motor to control the rate of rotation of the gears which drive the pulleys and belts 3|, and may be included in the circuit between the transformer and the switch SW. It is. also pos-- sible, as I have shown in Fig. 5, to include a rheostat RH in the circuit between the transformer and switch SW, so that it can be utilized to vary the speeds of the motor. This of course is optional.

The operation of the machine will perhaps be better understood after reference is had to Fig. 6, wherein the intake end of the frame I8 is shown provided with a bracket 15 extending upwardly therefrom at an angle of inclination and having a smooth inclined wall 76 along which flat work or articles may be fed into the machine for stacking. The bracket 75 also supports a plate Tl hingedly connected to the bracket at 18, so that it may be swung into the plane of and into alinement with the wall 16 as a continuation thereof to terminate adjacent the discharge belt 19 of the flat work ironer, designated generally by the letters FWI. Since the flat work ironer is of known construction, I will not go into the details of the construction and operation thereof, except to state that towels or other sheet materials being discharged from the flat work ironer by the belt l9 will slide down the chute provided by the smooth surfaces of the parts TI and I6, and then between the belts 3| and boards 36, to be gripped therebetween to be fed along the boards toward the superstructure or housing I8. As soon as the forward ends of the towels pass between the cylinder 48 and contacts 55, the solenoid S is de-energized because the circuit controlling the relay switch is broken, due to the fact that current cannot flow from one contact 55 to the other through the cylinder .1 38, as explained in connection with Fig. 5.

Therefore, the towels or other articles are held between the belts 35 or boards and plates 36 and slide along the said boards with the belts. As soon as the rear ends of the towels pass the contacts 55, the contacts engage the cylinder 48, so that the solenoid is energized moving the plunger 44 down and also the actuating rods 48 and links 3'! swinging the boards 36 on their hinges 35 to inclined position shown in dot and dash lines in Fig. 1, whereby the towels or other articles are released and may drop onto a support of any desired type. It will be understood that when the first towel or other article has passed the contacts 55 the second one is appreaching and the action of the apparatus is such that the cross-beam ll and actuating rods 48 are quickly raised to restore the plates or boards 36 into contact with the belts 3| to grip and convey the next towel or article in the same manner as the preceding one.

The time required to advance each article depends, of course, on the lengths of the articles, and the rate of movements of the belts.

Any suitable type of support may be provided beneath the boards 36 and the space therebetween to receive the towels or other articles when released in the manner above described. In other words, there may be a plain table, or a continuous or movable conveyor which will carry the towels away at predetermined intervals; but in the present application I have illustrated a support which permits of stacking a great number of towels or other articles thereon, and wherein each successive towel is dropped substantially the same distance from the boards 36 during the stacking.

In Fig. 1, the top of the support is designated by the numeral 88 and is of a width wider than the space between the belts 3i andalso wider than the towels or articles designated by the with a single fiat work ironer.

letter T, and also longer than the boards 36 and the towels or articles to be stacked. The top 80 has secured to its underside at the corners thereof, sockets 8| into which are threaded the ends of pipes or tubings 82 which are slidably mounted in the sleeves l5. Coil springs 83 are mounted in the tubings 82 and sleeves l5, and at their lower ends engage the sockets I! and at their upper ends engage the underside of the top 80, and hold the tubings 82 in telescoping relation to the sleeves I with the lower ends of the tubings normally elevated. As the towels or other articles are deposited successively on the top 80, the weight thereof compresses the springs 83 and moves the tubings 82 downwardly in the sleeves I5. Thus, the towels may be piled or stacked on the top 88 with the uppermost towel always being deposited or dropped the same distance as the preceding towel. When the stack or pile of towels is removed from the top 88, the springs 83 move the top 88 and tubings 82 upwardly restoring the top to normal maximum elevated position relative to the boards 36.

In Fig. 7, I have shown diagrammatically how a plurality or battery of the stacking machines above described, may be arranged to cooperate In Fig. 7, the stacking machines are designated generally by the letters SM and the flat work ironer generally by the letters FWI. The rollers 85 of the flat work ironer are of considerable length, so that they may simultaneously press or iron a plurality of parallel lines of towels or other articles, and as illustrated, there are six of the stacking machines to receive six lines of towels or other articles passing between and from the rollers 85 to the stacking machines.

I wish it to be understood that the stacking machines can be constructed to handle various sizes and types of articles, and that while I have described the invention particularly in connection with towels, it should be obvious that Various other types of sheet materials can be handled and stacked thereby whether fed from a fiat work ironer or from any other type of machine in which the articles are made, treated, or prepared.

In Fig. 8, I have shown a modification of the invention, wherein instead of providing the relatively movable electrical contacts between which the articles pass, I substitute therefor a photoelectric eye to make and break the circuit to control the solenoid. In Fig. 8, the primed numerals designate the corresponding parts of Figs. 1-6 designated therein by unprimed numerals. A platform or support 86 is mounted across the frame It! above the pulleys 26' adjacent the intake end of the frame. The light source LS is mounted on the underside of the cross-piece 52' and projects the ray of light through an opening 8! in the said cross-piece upwardly toward the photoelectric relay 88. The light source and photoelectric relayare of known construction and commercially available on the market, and have been in general use on other apparatus for controlling electric circuits. The photoelectric relay 88 includes the usual phototube, amplifier and relay to control the circuits actuating the solenoid, shown and described in Figs. 1, 3 and 4. A phototube shield 89 is mounted through the support 86 and the beam of light projected by the light source LS, when no article is interposed between the light source LS and the photoelectric relay 88, is projected through the shield 89.

The operation of the apparatus shown in Fig. 8 is the same as that described in connection with to the disc 9t.

' with three chambers.

I (not shown).

Figs. 1-7, namely, so long as the ray of light projected from the light source LS enters the photoelectric relay 3%, the solenoid is energized and the supports 36' are lowered. However, as the articles pass between the light source LS and the photoelectric relay 88, the ray of light is interrupted thereby and the solenoid is deenergized, whereupon the springs 43 of Fig. 1 return the cross head M to elevated position raising the supports 33 so that the articles may be fed therealong by the belts 3i. Obviously, as soon as the article has passed the opening 3? through which the ray of light is projected from the light source LS, use solenoid is again energized and lowers the supports 38 releasing the article in the manner previously specified, the operation being continuous or successive so that the articles are stacked one on the other.

While I have thus far illustrated and described the invention only in connection with automatically controlled electrically actuated means for effecting the stacking of the articles, I Wish it to be understood that I do not limit the invention to electrically controlled or actuated means, and in Figs. 9 and So, I have shown mechanically controlled means, which similar to the electrically controlled means, is actuated by the movements of the articles.

In Fig. 9, a wheel or disc corresponding to and located similarly to the disc 68 of Fig. l, is keyed to the shaft 22" which corresponds to the shaft 22 of Fig. 3, and 22 of Fig. 8. Beneath the disc 98 is a roller 9i mounted on a pin 92 carried by a bracket 93 which is mounted on top of a lever 5:1 fulcrumed at 95 on brackets 95 on a fixed support 5?. A coil spring 98 is disposed between the plate 527 and the lever 94 normally urging the lever upwardly and thereby urging the roller 9i towards and into operative relation with respect The free end of the lever 94 rests on a stem at which extends through an opening in gland nut Idii mounted in a valve casing Isl. The casing is! is provided with a chamber I532, in the lower portion of which is formed a port or seat wt for a ball It'l disposed in alinement with and engaged by the lower end of the stem 89. The chamber 522 communicates through the port I03 with a passage let: in the casing, and also communicates above the port I63 with a similar passage its in the casing. A pipe or conduit HT is connected with a source of air under relatively low pressure, not shown, and communicates with the passage IE5. Another pipe I98 communicates with the passage Iilt and is con- "nected into the top 85%? of a controller C. A flexible diaphragm I It forms with the top I69 of the controller a chamber 5 II into which the pipe I68 leads. The diaphragm M53 is connected tothe head H2 of a valve rod H8 which is surrounded by a coil Spring El i mounted between the head IE2 and the bottom of chamber H5 in the controller. The spring normally holds the head H2 and diaphragm Iii in a predetermined elevated position. The base of the controller is formed The upper chamber H6 has connected thereto a pipe I II which leads out to the atmosphere. Lower chamber I I8 has leading thereinto a pipe IE9 which is connected with a source of air under relatively high pressure Intermediate chamber I20 1s selectively communicable with the upper and lower chambers through ports I2! and I22, respectively. The stem i 53 isprovided at its lower end with a-valve head I23 to close the port I22, and thereabove with another valve head I24 to close the port I2I. The said valve heads are so spaced and arranged that when one of them is in closed relation to one of the ports, the other is in open relation to the other of the ports. This operation will be explained in detail hereinafter.

A pipe or conduit I25 leads from the chamber I2I into cylinder I26, as shown in Fig. 9a, the connection being made through the head I21 which closes the top of the cylinder and which is provided with an opening to receive the shaft I28 of piston I29. The cylinder I26 is mounted on a base I383 supported by the superstructure I9 corresponding to the superstructure I9 of Fig.

1. A packing ISI is provided in an over-sized bore in the head I21 around shaft I28 and is compressed by a gland nut I32 screw threaded into the head I21 and through which also extends the shaft I28. At its top the rod I28 is connected to the cross-head 4i corresponding to the cross-head 4| of Fig. 1, and connected at its opposite ends to actuating rods 19' corresponding to the actuating rods 48 of Fig. 1. Coil springs 13 normally hold the cross-head AI in elevated position, so that the movable supports along which the articles are moved are held in elevated position during the passage of the articles therealong, as previously described. I would explain that in Fig. 9a, the springs are shown compressed and the cross-piece II is in its lowermost position, at which time the piston H9 is at the bottom of cylinder I26.

With the foregoing in mind, the operation of the apparatus shown in Figs. 9 and 9a is as follows:

As the articles enter the machine in the man- 85 ner described in connection with Figs. 1-6, they pass between the disc 9i and the roller 9I, moving the roller down, whereupon the lever 94 depresses the stem 99 and seats the ball I64 in port I533. This cuts oiT the supply of air through pipe Nil, passages I65 and Hit, and pipe I98 into chamber III, so that the diaphragm H9 is in raised position. This causes the valve head I23 to close the port E22, so that the air under relatively high pressure cannot pass from pipe H9 to pipe I25 and consequently to cylinder 526. When this condition exists the springs 23' maintain the cross-head 4| elevated, and the movable supports along which the articles are moved, are also held elevated. As soon as each article passes from between disc 99 and roller SI, the spring 98 raises the lever 9 whereupon air under pressure enters through pipe I21 and passage I95 beyond ball I94, which is raised by the entering air, and then through pipe Hi8 into chamber l i i, depress- 65 ing the diaphragm Iii}. This downward movement of the diaphragm lowers stem H3 and seats valve head I24 in port I2I, while simultaneously lowering valve head I23 from port I22 to the full line position of Fig. 9. Consequently air under relatively high pressure enters through pipe H9 through chamber I98 and port i22, passage I'Et and pipe I25 into cylinder I26 depressing the piston I29 and consequently lowering the cross-beam iI', whereupon the supports along which the articles are moved are lowered and deposit the articles for stacking in the same man ner as described in connection with Figs. 16.

In Fig. 10 I have shown a simple form of light sensitive electrical apparatus, or Wiring diagram therefor, to control the stacking of the articles by operating the movable supports, which of course are preferably of the same construction and arrangement as those previously described and shown and wherein the supports are j normally held in gripping relation to receive the articles and move them to the point where they are to be stacked, at which point the solenoid is energized to effect separation of the supports to release the articles and eifect the stacking.

In Fig. 10 the letters LS indicate the same light source as in Fig. 8 and includes a lamp LA, the rays of which are projected upwardly toward the photoelectric cell or tube PhT which is connected by wires its, E36 to the usual amplifier I31, also connected by wires B33 and 839 to relay winding Hill of the relay Ml. A movable contactHlZ of the relay is connected by wire M3 to a source of current supply while fixed contact I 42' is connected by a wire M l to the solenoid [45, similar to and controlling the same parts as the solenoid S0 of Figs. 1 and 5. The winding of the solenoid M5 is also connected by a wire hit to the other side of the source of current supply.

Obviously as a towel or other article T, shown diagrammatically in Fig. 10, enters the apparatus at the inlet end as shown in Fig. 8, it prevents the passage of the rays from the light source LS to the photoelectric cell or tube PhT so that the circuit is interrupted due to the fact that the relay lei is not energized and the contacts M2, I43 are separated or are in the full line position of Fig. 10. The rays passing from the light source toward the photoelectric cell or tube are indicatedin dot and dash lines in Fig. 10, and obviously when there is no object interposed between the light source and the photoelectric cell or tube a circuit is completed through said tube, Wires I35, E36, amplifier it'l, wires E38, N39, energizing the relay Ml and drawing the movable contact M2 down, whereupon the solenoid M5 is energized, and in the manner previously de scribed causes separation of the supports on which the articles are moved depositing the articles at a predetermined point.

The arrangement described in connection with Fig. 10 is not my own invention, but is only illustrative. Of course I may use any other suitable wiring diagram for effecting the operation of my apparatus by light sensitive tubes or cells.

While I have shown and described two forms of electrically controlled apparatus, and only one form of mechanically controlled or operated apparatus, I wish it to be understood that the several embodiments of the invention shown and described are illustrative, and that various other types of electrically controlled and mechanically operated means may be employed without departing from the spirit of the invention and the scope of the appended claims.

I claim:

1. In apparatus for stacking sheet articles, cooperating members to grip opposite sides of the articles, one of said members being movable along the others to advance the articles therealong, and electrically actuated means controlled by the movements of the articles to cause said other members to be moved from gripping relation relative to said first members and articles therebetween to effect deposit of the articles at a predetremined point in their path of travel.

2. A machine for stacking sheet articles comprising a frame, a pair of spaced supports hingedly mounted on the frame at opposite sides thereof, a pair of endless belts or the like movable along said supports and adapted to grip the sheet articles against said supports and slide them therealong, an electric circuit, electrical contacts at one end of the frame connected in said circuit and between which the articles pass to control said electric circuit, and means controlled by said circuit to effect swinging movement of the supports relative to said belts to" effect release and deposit of the articles when they have passed through said contacts.

3. A machine for stacking sheet articles comprising a frame, a pair of spaced supports hingedly mounted on the frame at opposite sides thereof, a pair of endless belts or the like movable along said supports, means normally holding the supports in position to engage said belts and to grip opposite edges of the sheet articles therebetween, an electric circuit, electrical contacts at one end of the frame connected in said circuit and between which the articles pass to control said electric circuit, and means controlled by said circuit to effect movement of the supports away from the belts when the articles have passed said contacts to effect release and deposit of the articles successively one on the other.

4. In a sheet article stacking machine, means to grip opposite edges of the articles and to advance them successively in a common direction, electrically controlled means to effect relative movement between said gripping means to effect release of said articles successively from said gripping means, and means engageable by the articles to operate said electrically controlled means.

5. In a machine for stacking sheet articles comprising a frame, a pair of spaced supports hingedly mounted on the frame adjacent opposite sides thereof, a pair of endless belts or the like movable along said supports and adapted to grip the sheet articles against said supports and slide them therealong, means normally urging said supports toward and into gripping relation with the belts and articles therebetween, an electric circuit, electrical contacts at one end of the frame connected in said circuit and between which the articles pass, a solenoid operable by said circuit, and means operable by said solenoid to effect swinging movement of thesupports away from the belts to effect release and deposit of the articles.

6. A machine for stacking articles and including a frame, a pair of spaced supports movably supported on the frame to receive the articles, a pair of endless belts or the like movable above said supports and adapted to engage the articles and grip them against the supports to move the articles along said supports, means normally holding said supports in gripping relation with the belts and articles therebetween, and means operable by movement of the articles to effect relative movement between the supports to cause the supports to be moved out of gripping relation with the belts and articles to effect deposit or stacking of the articles.

7. A machine for stacking sheet articles comthe supports in gripping relation to the belts,

means to move the supports out of gripping relation relative to the belts to effect deposit or stacking of the articles, and a member engageable by said articles to control said last means.

8. A machine for stacking sheet articles comprising a frame, a pair of supports hingedly mounted on the frame in spaced relation toeach other, a pair of endless belts or the like movable along said supports and adapted to grip the sheet articles against said supports andslide them therealong, a superstructure at one end of the frame, means supported by said superstructure, normally holding the supports in gripping relation relative to the belts, an electric circuit, a solenoid supported by said superstructure and. connected in said circuit to move the supports out of gripping relation relative to the belts, and means at the other end of the frame controlled by the passage of the articles relative thereto to make and break said circuit and to control said solenoid.

9. A machine for stacking sheet articles comprising a frame, a pair of spaced supports along which the articles move hingedly mounted on the frame, means to grip the articles against said supports and move them therealong, means connected to the supports to move them on their hinges to effect swinging movement thereof to deposit the articles at a predetermined time, comprising a pair of links one connected to each support,

means normally holding said links in position to,

maintain the supports in position for movement of the articles therealong, and means controlled by movement of the articles to effect movement of the links to swing the supports on their hinges into article releasing position.

FREDERIC B. CLARK. 

